diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2014-09-21 20:41:53 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2014-09-24 15:15:38 +0200 |
| commit | 0ad6e3c5199be12c9745da8f8b9e3c9f8066c235 (patch) | |
| tree | 581d938c3bf976c54a95b2fd6030c232b7885031 /arch/x86/lib/thunk_64.S | |
| parent | f3670394c29ff3730638762c1760fd2f624e6d7b (diff) | |
x86: Speed up ___preempt_schedule*() by using THUNK helpers
___preempt_schedule() does SAVE_ALL/RESTORE_ALL but this is
suboptimal, we do not need to save/restore the callee-saved
register. And we already have arch/x86/lib/thunk_*.S which
implements the similar asm wrappers, so it makes sense to
redefine ___preempt_schedule() as "THUNK ..." and remove
preempt.S altogether.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140921184153.GA23727@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/lib/thunk_64.S')
| -rw-r--r-- | arch/x86/lib/thunk_64.S | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/x86/lib/thunk_64.S b/arch/x86/lib/thunk_64.S index 92d9feaff42b..b30b5ebd614a 100644 --- a/arch/x86/lib/thunk_64.S +++ b/arch/x86/lib/thunk_64.S @@ -38,6 +38,13 @@ THUNK lockdep_sys_exit_thunk,lockdep_sys_exit #endif +#ifdef CONFIG_PREEMPT + THUNK ___preempt_schedule, preempt_schedule +#ifdef CONFIG_CONTEXT_TRACKING + THUNK ___preempt_schedule_context, preempt_schedule_context +#endif +#endif + /* SAVE_ARGS below is used only for the .cfi directives it contains. */ CFI_STARTPROC SAVE_ARGS |